Self sustaining paper punch frame assembly



April 30, 1963 L. H. SEMLER SELF SUSTAINING PAPER PUNCH FRAME ASSEMBLY Filed June 30, 1958 7L 6 w# we lNVENTOR' 52m m (7%, A 7'7'0RNE V5.

United States Patent Ofiiice 3,087,367 Patented Apr. 30, 1963 3,087,367 SELF SUSTAINING PAPER PUNCH FRAME ASSEMBLY Loren H. Semler, Chicago, lllL, assignor to Metal Specialties Manufacturing (30., Chicago, 111., a corporation of Illinois Filed June 30, 1958, Ser. No. 745,569 2 Claims. (Cl. 33583) This invention relates to a punch, and, more particularly, to a punch for forming perforations in paper and other forms of web. Certain phases of the invention may be employed with various types of punches and punch apparatus.

In the structure of punch apparatus in which punch plungers are slidably mounted in supports, the alignment of the parts so that the holes in the supporting apparatus will lie in the true axis of the plunger, is of the utmost importance. In the fabricating of punch apparatus, it is important that the parts be formed by inexpensive operations and then readily brought together for assembly, which can be accomplished expeditiously while bringing the parts in true alignment. Further, in such apparatus, the formation of the punch itself so that its cutting edges shear the paper accurately without distorting it in the cutting operation, is of great importance.

An object of the present invention is to provide a punch and punch apparatus in which the parts are accurately aligned and held in true alignment while at the same time effectively shearing paper and other web material in a punch operation. A further object is to provide a punch having a bottom area of unusual contour in which an effective shearing action is brought about with a minimum of force and while obtaining cleancut punched segments. Yet another object is to provide a method and means of forming a punch in which the parts brought together and secured are accurately aligned for the punching operation and in which the parts are held securely during repeated operation of the punch. Other specific objects and advantages will appear as the specification proceeds.

The invention is shown, in an illustrative embodiment, by the accompanying drawing, in which FIGURE 1 is a perspective view of a punch embodying my invention; FIG. 2, a vertical sectional view, the section being taken as indicated at line 22 of FIG. 1; FIG. 3, a vertical sectional view, the section being taken as indicated at line 3'3 of FIG. 2; FIG. 4, a perspective view showing the several parts in spaced-apart relation and prior to assembly; and FIG. 5, a view of the bottom portion of the punch shown in inverted position and illustrating the inclination and concavity of the bottom Wall of the punch.

In the fabrication of the punch structure, I preferably form perforations in a fiat strip of metal, cut the strip into segments, form the segments into U-shaped members, and then assemble the U-shaped members together as illustrated in FIG. 4.

The assembled structure shown in FIG. 1 comprises a U shaped member having a central base portion 11, an upper leg portion 12, and a lower leg portion 13. The other U-shaped member 14 comprises a central base portion 15, an upper leg portion 16, and a lower leg portion 17.

The base portion 11 of member 10 is provided with a recess 18, as shown best in FIG. 4, and the lower leg 17 of the U-shaped member 14 is provided with a tongue 19 adapted to engage the recess 18. The engagement of the tongue 19 with the recess 18 spaces the leg 17 above the leg 13 so as to provide therebetween a paper-receiving recess 20, as shown best in FIG. 2.

In the assemby of the U-shaped members 10 and 14, I prefer to provide the upper leg 12 of member 10 with alignment pins or points 21 adapted to engage the openings 22 of the upper leg 16 of member 14 so that the U-shaped members are thus quickly aligned and the parts may then be spot-welded along the points 21 and openings 22 to permanently secure the parts together.

The performations which have heretofore been referred to and which are accomplished preferably before the flat strip is cut into segments and formed into the U-shaped members, will now be described. A relatively small opening 23 is formed in the upper leg 16 of member 14, and a similar opening 24 is formed in the upper leg 12 of member 10. A larger opening 25 to receive an enlarged portion of a punch is formed in the lower leg 17 of the member 14, and a similar large opening 26 is formed in the lower leg 18 of member 10.

The punch 27 has an upper reduced portion received within the openings 24 and 25 of legs 16 and 12, and a punch cap or head 28 is secured upon a still further reduced portion 29 of the punch by a swaged head 30. A spring 31 normally urges the head 28 toward raised position. The lower portion 32 of the punch is enlarged and is adapted to reciprocate through the openings 25 and 26 of the legs 17 and 13.

The bottom of the punch 32 is formed to provide both an inclination and a concavity. Heretofore, it has been common to employ a punch having a tapered bottom and also a separate punch having a grooved bottom surface. I have discovered that where a single punch bottom is provided not only with an inclined surface but also simultaneously with a concave or grooved surface, far greater cutting efficiency is obtained in that the cutting begins at a single point and a progressive shearing action thereafter occurs without the paper or other web engaging the central port-ion of the punch. As a result, the force required to cut through one or many sheets of paper, etc., is greatly reduced because the initial cutting begin-s atone point and the cutting proceeds progressively around the periphery of the punch bottom until the cutting is consummated. In the structure shown, the bottom of the punch is tapered to a point 34, while at the same time the bottom of the punch is grooved, preferably in the direction of the taper, to form a central concavity 35. Thus, the completed punch has a point or long portion '34, and opposite thereto a short side 36, and, intermediate these portions, as shown by dotted lines in FIG. 2, there is a groove or concavity 35.

In the operation of the punch apparatus illustrated, a long strip of metal is punched to form perforations which have been described as well as the aligning pins 21 and the alignment openings 22, and, after the strip is cut to form segments and the segments formed into U-shaped members, as shown best in FIG. 4, the parts are brought together in assembled relation with the tongue 19 of leg 17 engaging the recess 18 of base 11 and the parts welded along the alignment elements 21 and 22 to form a completed structure in which the legs 17 and 13 provide between them a paper-receiving recess. Prior to the welding operation, the punch is inserted in position, as illustraded in FIGS. 2 and 3, "and thereafter the spring 31 is placed about the reduced stem of punch 27 and the cap 28 secured in place, as heretofore described.

In the punching procedure, a web or several plies of web are inserted within the recess 20 and the cap 28 pressed to move the cutter 32 downwardly. The point 34 of the cutter first engages the web and a progressive shearing action follows in which the circular cutting edges of the hollow bottomed punch cut the web without any substantial engagement between the web and the central concave portion of the punch bottom.

In the illustration which has been set out, an extremely simple form of punch has been shown, but it will be understood that the invention herein may be employed with d-ifierent forms of punch structures and in different combinations.

While, in. the foregoing specification, I have set forth a specific structure in considerable detailfor the purpose of illustrating an embodiment of the invention, it will be understood that such details of structure may be varied widely by those skilled in the art without departing from the spirit of my invention.

Iclaim:

.1. A-punch,icomprising two U-shaped members, each having U-legs connected by a base, one of said U-members having its base provided with a tongue-receiving apertureat a. spaced distance .above its lower U-leg and the other of said.U-mem-bers having its lower U-leg provided witha forwardly-projecting tongue, the lower U-legs .of said members being provided with large openings and each other and providing with aligned small openings, said U-members thereby providing a sel-fsustaining frame assembly, a head-equipped punch having an upper reduced portion received within said aligned openings in said upper U-legs and a lower enlarged portion received within the openings in the lower U-legs of said members, said apertured base having a portion thereof between the lower U-legs of said members defining a back gauge for limiting the extent of insertion of sheet material between said lower legs, and a spring between the upper legs of said members and said punch head urging said punch to an elevated position.

2. The structure of claim 1 in which the upper U-legs of said members are welded together.

References Cited in the file of this patent UNITED STATES PATENTS 562,981 Sprinkle June 30, 1896 1,783,063 Vienneau Nov. 25, 1930 2,368,790 Unger Feb. 6, 1945 2,671,951 Sliviak Mar. 16. 1954 2,726,721 1Segal Dec. 13, 1955 2,749,816 Jewell June 12,1956 2,825,407 Widell Mar. 4, 1958 2,883,228 Roberts Apr. 21, 1959 FOREIGN PATENTS 198,071 Germany Mar. 24, 1907 

1. A PUNCH, COMPRISING TWO U-SHAPED MEMBERS, EACH HAVING U-LEGS CONNECTED BY A BASE, ONE OF SAID U-MEMBERS HAVING ITS BASE PROVIDED WITH A TONGUE-RECEIVING APERTURE AT A SPACED DISTANCE ABOVE ITS LOWER U-LEG AND THE OTHER OF SAID U-MEMBERS HAVING ITS LOWER U-LEG PROVIDED WITH A FORWARDLY-PROJECTING TONGUE, THE LOWER U-LEGS OF SAID MEMBERS BEING PROVIDED WITH LARGE OPENINGS AND SAID UPPER U-LEGS OF SAID MEMBERS BEING PROVIDED WITH INTER-LOCKING PINS AND PIN RECESSES, SAID PIN RECESSES SNUGLY RECEIVING SAID PINS THEREIN, SAID FORWARDLY-PROJECTING TONGUE BEING SNUGLY RECEIVED WITHIN SAID APERTURE FOR SUPPORTING THE UPPERMOST OF THE LOWER U-LEGS AT A SPACED DISTANCE ABOVE THE LOWER U-LEG OF THE OTHER MEMBER, SAID LOWER U-LEG OF SAID OTHER MEMBER HAVING SHOULDERS ADJACENT SAID TONGUE ENGAGING THE BASE OF SAID ONE MEMBER ADJACENT SAID APERTURE, SAID U-MEMBERS HAVING THEIR UPPER U-LEG OVERLAPPING AND IN SURFACE ENGAGEMENT WITH EACH OTHER AND PROVIDING WITH ALIGNED SMALL OPENINGS, SAID U-MEMBERS THEREBY PROVIDING A SELF-SUSTAINING FRAME ASSEMBLY, A HEAD-EQUIPPED PUNCH HAVING AN UPPER REDUCED PORTION RECEIVED WITHIN SAID ALIGNED OPENINGS IN SAID UPPER U-LEGS AND A LOWER ENLARGED PORTION RECEIVED WITHIN THE OPENINGS IN THE LOWER U-LEGS OF SAID MEMBERS, SAID APERTURED BASE HAVING A PORTION THEREOF BETWEEN THE LOWER U-LEGS OF SAID MEMBERS DEFINING A BACK GAUGE FOR LIMITING THE EXTENT OF INSERTION OF SHEET MATERIAL BETWEEN SAID LOWER LEGS, AND A SPRING BETWEEN THE UPPER LEGS OF SAID MEMBERS AND SAID PUNCH HEAD URGING SAID PUNCH TO AN ELEVATED POSITION. 